NASA is struggling with money for more Earth scientific projects.

 By Jeff Foust - January 6, 2023

The Terra, Aura, and Aqua missions will be invited to the forthcoming senior review of prolonged Earth science missions, but NASA has issued a warning that the organisation does not have the resources to support all projects that request extensions. Source: NASA

In Washington Even as the organisation warns of budget limitations on its overall portfolio of missions, NASA will let three elderly Earth science programmes to take part in an upcoming senior assessment of extended missions.

NASA representatives announced that the agency has asked the Aqua, Aura, and Terra missions to make recommendations in the 2023 senior review of Earth science projects that are in their extended stages during a town hall on December 15 at the Fall Meeting of the American Geophysical Union.

The three spacecraft, which were launched between 1999 and 2004, are still operable but are out of fuel for stationkeeping. Concerns have been raised about how this will affect the science the spacecraft can conduct and the integrity of their data. The spacecraft have begun to drift from their original operational orbits.

In November, NASA held a virtual workshop with more than 500 participants to get comments on those missions, according to Julie Robinson, deputy director of the Earth science division at NASA. She said that Terra, Aqua, and Aura will be invited to the senior review as one result of this. Senior reviews present the argument for ongoing funding to prolong missions that have finished their intended main missions.

However, participation in the senior review does not ensure that the missions will be able to obtain financing. Given the little money for mission extensions, Robinson predicted that the impending senior review will be extremely difficult.

This year's senior evaluation won't be simple, she predicted. We lack the funds in the budget to continue every mission that is brought up for senior assessment. The agency will consult the panel that evaluates the mission for suggestions on other mission trade-offs it may make.

In its budget request for the next fiscal year 2023, NASA asked for more than $2.4 billion for Earth science. However, Earth science received slightly less than $2.2 billion from the omnibus budget measure that was passed in late December. Even though it is a $130 million increase from 2022, the increase coincides with NASA stepping up work on its line of Earth System Observatory missions and other programmes.

A scientist at the town hall remarked that it was "quite astonishing" that NASA would even consider terminating those three missions, considering their success and the number of researchers who use the data they collected. Robinson once more focused on the program's general financial difficulties.

One of the difficulties we have with Terra, Aqua, and Aura is that these systems are quite expensive since they have been in use for such a long time. According to NASA's fiscal year 2023 budget request, Terra, Aqua, and Aura operations would cost $30.7 million apiece, while Terra operations would cost $20.5 million. She did provide an estimate of the range of possible savings, but one aspect of the senior review will be to look at lowering those operational expenses.

The Earth System Observatory, particularly the Atmospheric Observing System, may incur cost increases, and NASA is now assessing these possible cost increases (AOS). AOS as it is now built is anticipated to cost $2.4 billion, which is $500 million higher than NASA had originally estimated. That may compel NASA to replace or reduce the size of two AOS sensors.

"Trades in Earth System Observatory may be quite unpleasant. Additionally difficult trade-offs must be made when determining how much funding to allocate for lengthy missions. "I can guarantee that with those transactions, nobody will ever be satisfied."